| Abstract: | To obtain the peak response at 532 nm,narrow-band response GaAlAs photocathodes with two GaAlAs active layers of different aluminum compositions are designed in consideration of the maximum absorptivity and quantum efficiency.The transmission-mode and the corresponding reflective-mode photocathodes are grown by metalorganic chemical vapor deposition.The results indicate that the peak response and the cut-off wavelength occur at 532 nm for the two kinds of photocathodes respectively.The response of the reflection-mode photocathode is an order of magnitude higher than that of the transmission-mode photocathode,whereas the better growth quality and the thicker second GaAlAs active layer can improve the transmission-mode response. |
